• Korean Journal of Ichthyology
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• v.28 no.1
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• pp.9-18
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• 2016

Histological and morphological development of the digestive tract of sevenband grouper were observed from after hatching to 60 days. Fishes were fed with rotifer (Brachionus rotundiformis) and chlorella (Chlorella ellipsoidea) after hatching from 2 to 20 days rotifer and brine shrimp (Artemia salina) in after 20 days rotifer, brine shrimp and semi-dry artificial diet in after 23 days. Histological and morphological development of ten larvae was observed by paraffin embedding method after fixing in 10% neutral buffered formalin. Sevenband grouper RLG showed characteristics of carnivorous fish by average 0.87. Larvae after hatching can't open the mouth and anus digestive tract was observed in a straight line following yolk sac. Larvae was observed feeding activity by opening the mouth and anus. Metamorphosis started 8 days after hatching. Esophagus divided four layer, and goblet cell was observed in esophagus, mid intestine and rectum. Larvae started cannibalism and it was caused by difference of growth. The inside of stomach was differentiated to cardiac orifice, body of stomach, pyloric stomach, and pyloric caeca. Goblet cell was observed all intestine. Gastric gland differentiated after hatching 28 days in stomach. Secretion of gastric juice was found at stomach and mucosal fold pyloric caeca. Even thought the inside of stomach expended and the number of gastric gland increased consistently and goblet cell in intestine and mucosa became longer, histochemical changes follow couldn't be found during transforming juveniles 38 days after hatching.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.6
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• pp.798-802
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• 1999

This study was performed to compare the effect of enrichement of rotifer and Artemia fed marine bacteria (Erythrobacter sp. S$\pi$-1) with those fed the different diets-(Super Selco, $\omega$-yeast and marine Chlorella) on the slime flounder larvae, Microstomus achne. Because the ratio of docosahexaenoic acid (DHA) to fatty acids in rotifer (dry weight $\%$) fed on Super Selco and ESP-SR including Erythrobacter sp. S$\pi$-1 was higher than that in rotifer fed marine Chlorella, the growth of the slime larvae fed the former showed better than the latter. And the ratio of DHA and highly unsaturated fatty acid (n-3 HUFA) to fatty acids in Artemia (dry weight $\%$) enriched by ESP-A including Erythrobacter sp. S$\pi$-1 were also higher than those in Artemia enriched by others or Artemia without enrichment. Larvae fed on Artemia enriched by ESP-A showed better growth and survival rate than those fed on Artemia enriched by others or Artemia without enrichment. With regard to dietary value of Erythrobacter sp. S$\pi$-1, its use could improve the quality of the live foods for the slime flounder larvae.

• Journal of Aquaculture
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• v.13 no.1
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• pp.63-67
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• 2000

Tigriopus japonicus harpacticoida copepod was a common copepoda species as food organism for the marine fish larval rearing. However T. japonicus was difficult to stable culture except for a mixed culture with rotifer. Available food source for the successfully stable culture of T. japonicus was investigated in this study. T. japonicus did not utilization Nannochloropsis oculata instead of that. T japonicus utilized to products from rotifer culture tank. The products from rotifer culture tank was composed of rotifer feces and co-existing aquatic bacteria. The nauplius I stafe and copepodid I stage of T. japonicus showed grown whenproducts from rotifer culture tanks was fed. Specially we observed higher density of nauplii than that of copepodites and ovisac carrying females in the experimental culture populations.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2002.05a
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• pp.16-16
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• 2002

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.10a
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• pp.207-208
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• 2000

담수산 rotifer, Brachionus calyciflorus는 입의 크기가 작은 담수어 종묘생산시 자어의 초 먹이생물로 많이 이용되고 있다. 이들의 성장은 male의 출현 없이 폭발적으로 개체가 증가되는 처녀생식과 male의 출현으로 휴면란(내구란)을 생산할 수 있는 유성생식으로 나눌 수 있다. 특히, 유성생식에 의해 생성된 내구란은 종의 효율적인 보존 뿐만 아니라 Artemia cyst처럼 간단하게 부화시켜 자어에게 먹이로 공급할 수 있는 장점이 있다. (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.10a
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• pp.193-194
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• 2000

근래에 들어 어류 양식 분야가 활기를 띠면서 어류 종묘생산에 대한 관심도가 높아지고 있다. 그럼으로 인하여 먹이생물에 대한 중요성이 높아졌고 이에 대응하는 먹이생물의 연구가 많이 이루어지고 있다. 지금까지 먹이생물로 이용되어온 것은 chlorella와 rotifer, artemia 등이며 chlorella와 rotifer는 현재까지 배양하는데 별다른 문제가 없어 이용되고 있으나 artemia는 전세계적으로 생산이 급감하는 추세이며 우리 나라의 경우는 전량수입에 의존하여 국가적 손실이 크므로 이에 대한 대체먹이생물의 개발이 시급한 실정이다. (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.275-276
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• 2001

담수어류의 종묘 생산시 담수산 rotifer, Brachionus calyciflorus는 동물 먹이생물로 많이 이용되고 있다. 특히, 유성생식에 의해 형성된 이종의 내구란은 두터운 2차 난막으로 싸여져 있어 외부환경이 부화에 적합하지 않으면 강한 내구성을 지니고 있어 휴면상태를 계속 유지한다. 이러한 내구란은 종의 유전적 형질을 효율적으로 보관 할 수 있을 뿐만 아니라 대량배양용 seed와 생태 독성학의 실험재료로 이용할 수 있다. 또한 Artemia cyst처럼 쉽게 부화시켜 자어에 직접 공급할 수 있는 장점을 가지고 있다. (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.281-282
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• 2001

본 연구는 현재까지 국내에서 가숭어, Chelon lauvergnii의 성숙 및 인공 종묘 생산에 관한 구체적인 연구 보고는 매우 미흡한 실정임을 고려, 가숭어의 효과적인 인공 종묘 생산을 위한 기초 자료로서 산란기 특성 조사 및 부화 자어에 대한 rotifer, Artefnia, 배합사료 공급에 따른 성장과 생존을 조사하였다. 또한 rotifer와 brine shrimp, Artemia nauplius를 오징어 간유, 식물성 플랑크톤 건조 분말인 Maxima$^{TR}$ , Chlorella sp.로 각각 영양 강화한 후 치어에 공급시 자어의 성장과 생존에 대한 그 효과를 비교 분석하였다. 아울러 밀도별 사육 실험을 통한 적정 밀도를 규명하여 가숭어 종묘 생산시 효율적이고 경제적인 기술을 개발하고자 본 연구를 수행하였다. (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.387-388
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• 2001

근래에 들어 어류 양식 분야가 활기를 띠면서 어류 종묘생산에 대한 관심도가 높아지고 있다 그럼으로 인하여 먹이생물에 대한 중요성이 높아졌고 이에 대응하는 먹이생물의 연구가 많이 이루어지고 있다. 지금까지 먹이생물로 이용되어온 것은 Chlorella와 Rotifer, Artemia등이며 Chlorella와 Rotifer는 현재까지 배양하는데 별다른 문제가 없어 이용되고 있으나 Artemia는 전세계적으로 생산이 급감하는 추세이며 우리 나라의 경우는 전량수입에 의존하여 국가적 손실이 크므로 이에 대한 대체먹이생물의 개발이 시급한 실정이다(김 등, 1999). (중략)

• Fisheries and Aquatic Sciences
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• v.2 no.2
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• pp.182-188
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• 1999

Production of extracellular polysaccharide by Monilinia fructigena in B-I medium containing cereals was higher than that in glucose medium. Productivities in B-I medium and glucose medium were 0.7g/l nd 0.2-03g/l respectively. The maximum content of polysaccharide occurred at the rising point from the lowest pH of culture. As the apparent viscosity of the polysaccharide solution increased, the flow Index (m) decreased, and the consistency Index (Kc) also increased. The polysaccharide solution was a typical pseudoplastic fluid. The mycelium was separated from the culture solution by $300\mu m$ mesh-filter and the polysaccharide was precipitated by adding 50% of ethanol (v/v). The amount of the polysaccharide removed from the filtrated solution was 0.45 g/l and the amount adhered to the mycelium was 0.25g/l. In experiments for investigating growth enhancement of rotifer (Brachionus plicatilis) by the polysaccharide, the dose of the polysaccharide was 1mg per 10,000 organisms of rotifer. Maximum specific growth rate of rotifer with feed consisting of sea Chlorella sp. and the polysaccharide was 1.095/day in the batch culture for 10 days. A semi-continuous culture was done for 30 days, the biomass of rotifer could be harvested twice. Maximum specific growth rate with sea Chlorella sp. and the polysaccharide was 0.734/day before the first harvest, and 1.685/day before the second harvest. Productivity was 38 $cells/ml\; \cdot\; day$ with sea Chlorella sp. and the polysaccharide.